The present invention relates broadly to motion upholstery furniture designed to support a user's body in an essentially seated disposition. Motion upholstery furniture includes recliners, incliners, sofas, love seats, sectionals, theater seating, traditional chairs, and chairs with a moveable seat portion, such furniture pieces being referred to herein generally as “seating units.” More particularly, the present invention relates to an improved linkage mechanism developed to accommodate heavier loads carried on a seating unit, which are otherwise limited by the configurations of linkage mechanisms in the field. Additionally, the improved linkage mechanism of the present invention may be composed of standard sized parts rather than over-sized high-strength parts. As a result, the improved linkage mechanism may be assembled from parts manufactured on the same manufacturing line as parts used for traditional-load seating units rather than made on a separate manufacturing line.
Recliners are generally well known in the furniture industry. The term recliner is used throughout this description to describe articles of furniture that include a reclining mechanism. Generally recliners are chairs that allow the user to recline and are equipped with extendable footrests. Recliners can also comprise any of the different seating units described above. Recliners are known in both a manual configuration (where the user releases the reclining mechanism from a closed position to a TV position, and moves the reclining mechanism from the TV position to a fully reclined position) and a motorized version (where a motor is used to move the mechanism between the various positions).
The reclining motion is achieved in recliners with a linkage mechanism that is coupled to a base. The linkage mechanisms found in recliners in the art include a plurality of interconnected links that provide one or more mechanisms for extending a footrest, reclining the recliner, and obstructing movements of the chair when in specific orientations. Typically, recliners known in the art provide three positions: an upright seated position with the footrest refracted beneath the chair (the “closed position”); a television viewing position in which the chair back is slightly reclined but still provides a generally upright position with the footrest extended (the “TV position”); and a fully reclined position in which the chair back is reclined an additional amount farther than in the TV position but still generally inclined with respect to the seat of the chair and with the footrest extended (the “fully reclined position”).
These types of prior art recliner mechanisms, while functional, typically have a maximum load rating above which the seating unit cannot successfully operate over the entire expected useful life of the seating unit. As humans have grown larger, the furniture industry has responded by designing seating units capable of carrying even heavier loads. Most recently, recliners have been made that can carry up to 350 pounds using conventional parts and materials. In situations where it is desirable to provide a recliner capable of carrying a load above the maximum load rating, special bariatric seating units have been designed. These special bariatric seating units include reclining mechanisms made from different materials and components having increased sizes from that of traditional-load recliners in order to accommodate the increased load. As a result, different materials, which are often more expensive, and more of them (i.e., thicker parts), to accommodate the increased component size, are required. Because of these differences, manufacturing these special bariatric seating units requires a different manufacturing line and different tooling to produce the different components and materials than the manufacturing line used for the traditional-load recliners, which is inefficient and expensive.